In the modern world the vast majority of clothing is made from woven fabrics, and the art of weaving is many centuries old. Indeed the invention of weaving is generally attributed to the Ancient Egyptians. Yarns were produced from natural cotton, wool, or linen fibers, and garments made from fabrics woven from these yarns often creased badly in wear and, when washed or dry cleaned, required considerable time and effort with a steam pressing machine or iron to restore them to a pristine appearance.
Dry cleaning is by classical definition a process of cleaning textiles in a nonaqueous liquid medium. Excessive amounts of wet solvents such as water and glycols tend to swell hydrophilic textile fibers causing dimensional changes in yarns, fabrics and garments. Dry solvents such as hydrocarbons and the halocarbons do not swell the textile fibers and they thus have no effect on the physical properties of the textile structure.
Dry cleaning appears to be an old art, with solvent cleaning first being recorded in the British Isles and Scotland in the 1860's. With the large-scale production of gasoline in the United States in the early 1900's, dry cleaning became a growing industry. By the 1930's the less flammable Stoddard solvent replaced gasoline in most dry cleaning operations.
Today, there are thousands of dry cleaning plants in the United States with an estimated annual volume of business in several billion dollars. In the sixties, thousands of self-service type dry cleaning stores were opened across the country.
Dry cleaning systems are closed systems. The systems are closed to prevent loss of cleaning solvent to the environment. Such a system restricts moisture and outside air from the system.